Method of vaporizing oil



Sept- 26, 1933 A. E. HARNSBERGER r-:r AL 1,928,102

rMETHOD OF VAPORIZING OIL Filed Feb. 28. 1928 Audley LMJMKMS U w Kw@ gwuentoz @fer Son Cornfl'us WM 777 W attoznui n FG ruk hubs Patented Sept. 26, 1933 PATENT OFFICE METHOD oF vAPoRIzrNG on.

Audley E. Harnsberger and Cornelius B. Watson,

Chicago, Ill., assignors to The Pure Oil Company, Chicago, Ill., a corporation of Ohio Application February 28, 1928. Serial No. 257,694

1 Claim.

This invention relates to an improved method of converting hydrocarbon compounds of relatively high boiling point into similar compounds of lower boiling point suitable for use as a mo-y tor fuel, and has particular reference to systems of cracking hydrocarbon compounds wherein such compounds while in the state of vapor are passed through a heating zone and raised to a temperature wherein molecular decomposition to a desired degree is effected.

It has been found that in the operation of high temperature vapor phase systems of cracking oil that at the point where the oil vapor enters the converter or other zone of high temperature, there is present, after a certainperiod of operation, a deposit of hardened coke or carbon on the inner walls of the converter elements through which the oil vapors travel. This carbon encrustation accumulates to such an extent that the converter tubes or elements become clogged, interfering with the How of the oil vapor and reducing heat conductivity to such an extent that it is necessary from time to time, and at more or less frequent intervals, to shut down the operation of the converter and clean the converter tubes or elements to remove the clogging carbon deposit therefrom.

In order to eliminate or minimize the formation of such carbon deposit on the inner walls of the converter tubes, we have discovered that by removing from the oil vapors, prior to conversion, all entrained liquid so that when the vapors enter the converter the said vapors are in a dry gaseous condition, greatly improved results in the elimination of carbon deposit are secured, with the result that more sustained op- V eration on the part of the system is obtained t-ogether with a greater recovery of gasoline fractions and a reduction in fixed gas formation. Other incidental advantages are present such as economy in the upkeep and operation of the system, freedom from overheated tubes and the avoidance of frequent converter shutdowns.

For a further understanding of the invention reference is to be had to the accompanying drawing, wherein:

Figure 1 discloses diagrammatically apparatus for converting oil inthe vapor phase and in accordance with the present invention;

Figure 2 is a vertical sectional view taken through the separator,

Figure 3 is a horizontal sectional view through said separator,

Figure 4 is a detail sectional view disclosing a slightly modifled form of separator.

Referring more particularly to the drawing the numeral 1 designates an oil heater which is formed to include a setting 2. ,'The setting is formed to provide converting -and vaporizing sections 3 and 4 respectively. Within the converting section of the setting there is disposed a bridge wall 5, which divides the converting section into combustion and tube chambers 6 and 7 respectively. Arranged Within the tube chamber are a pluralityof converting tubes 8, through which are passed oil vapors in order that such vapors may be subjected to the heat developed within the setting and brought to` conversion temperatures ordinarily in excess of 1000 Fah.

Leading from the converting section of. the setting is a flue'duct 9 which leads to the upper part of the setting of the vaporizing section 4. Within this section of the setting there is disposed a plurality of vaparizing tubes 10, which are swept by the furnace gases which are discharged from. the converter section by way of the duct 9.

Oil is first introduced in liquid form into the vaporizing tubes 10, where the oil is heated sufliciently to raise its temperature to approximately 700 Fah., wherein the lighter fractions of the oil are vaporized and the heavier fractions remain in liquid form. After leaving the tubes 10 the oil and oil vapors pass by way of a pipe line 11 to an evaporator 12 in which takes place a physical separation of the liquid and vapor. The liquids which do not vaporize at a temperature of between 650 to 700 Fah., are drawn olf from the bottom of the evaporator by way of a pipe line 13 and are permanently removed from the system. The vaporous fractions are led off from the top of the evaporator by way of a pipe line 14 and are introduced into the converting tubes 8 of the oil heater, wherein the temperature of these vapors is raised to a converting temperature in 'excess of 1000 Fah. After leaving the converter the oil vapors are condensed and suitably fractionated by any standard method, not shown.

In carrying out the present invention there is provided a separator 15 which is disposed in the pipe line 14 between the evaporator and the converter. The purpose of this separator is to remove a11 entrained liquid which iS present in the oil vapor as the latter is being transferred from the evaporator to the converter. As previously stated, by removing such entrained liquid and permitting only of the entrance of oil vapors in a dry gaseous form into the converter, 4we are enabled to eliminate or greatly reduce the formation of carbon or coke on the innerv walls of the converterv tubes 8 at positions where the vapors first enter the converter.

In securing this result the separator includes a cylindrical casing 16 in which is positioned a nest of relatively staggered rows of vanes or baiiies 17, which act to intercept the flowing vapor stream and particularly the entrained liquid therein. 'Ihis liquid contacts with the bailles 1'7, one after the other and is either vaporized or, ii not vaporized, runs down the length of the bales 17 and accumulates as a liquid in the bottom of the separator, where it may be removed by means of a pipe line 18. If desired, the casing may bel jacketed as at 19 for the purpose of permitting of the circulation of heated ue gases obtained from the converter or other heating medium such as superheated steam therethrough. By thus heating the separator the temperature of the oil vapor is raised sufciently to thoroughly dry the oil gases or vapors but not to a sufficient extent to produce any substantial cracking.

Another slightly modied form of separator has been disclosed in Figure 4, wherein the casing 20 is provided internally with an upstanding funnel 2l. The outer walls of the funnel are provided with helical baiiies 22. The oil vapor enters the top of 'the casing 20 and swirls rapidly around the helical baies 22, causing the liquid content thereof to accumulate on the inner Walls of the casing 20 and to gradually run down such walls and to accumulate in the bottom of said casing, where the liquid may be withdrawnby the pipe line 18. The vapors or gases remaining pass upwardly through the funnel 21 and are then led to the inlet side of the converter. Either type oil separator is quite eflicient in removing the liquid content of the oil vapor flowing between the vaporizing and converting sectionsof the heater. Other types of separators may also be used with equal effectiveness in obtaining the production of dry gases or oil vapors for the con-y verter.

superheated steam may be introduced in either the bottom or top, or both, of the evaporator 12, and also at a point between the vapor drier and separator 15 and the inlet of the converter. The entrance of the superheated steam into the evaporator is indicated at 23 and into the pipe line between the separator and converter is indicated at 24. It is preferred that the bulk of the superheated steam be admittedbetween the vapor drier or separator and the converter, since this will tend to materially reduce vapor velocities through the drier and secondly Will provide further drying action due to the decrease in partial pressure on the oil vapors at the point where the steam is admitted. Also, by rsuperheating the steam to, for example, 900 or 1000 Fah., or even higher considerable heat is added and in this Way the introduction of the steam provides for a further drying action. l

We, therefore, do not limit ourselves to the specic apparatus disclosed but reserve the right to employ all such modications of the invention as may be said to fall withinthe scope of the following claim.

What is claimed is:

The method of converting oil in the vapor 1 phase, the steps which consist in heating the oil to a temperature of approximately 650 Fah. to vaporize a portion thereof, subjecting the oil and oil vapor when at such temperatures to a primary stage of separation wherein the liquid lati 

